Traveling for July 4 holiday? Be prepared for busy airports

Los Angeles International Airport is expected to be one of the busiest for the July 4 holiday.

The busiest travel event of the summer will be especially hectic this Friday at Las Vegas, Los Angeles and Atlanta, according to numbers crunched by Hopper travel data, which has identified the 20 busiest airports for the long July Fourth weekend.

Travelers at other busy East Coast airports may face another problem: Tropical Storm Arthur, the first named storm of the season, which is heading north from Florida.

Air travel prices are running about 15 percent higher this July 4 over last year, and many of the top destinations are repeats from 2013, Patrick Surry, Hopper's chief data scientist, told CNBC. The forecast covers June 27 through July 6, with the busiest airport day falling on Friday, July 4, he said.

The busiest airports for the Fourth of July holiday travel will be:

1. Las Vegas (LAS)

Los Angeles (LAX)

Atlanta (ATL)

Chicago (ORD)

Denver (DEN)

Newark (EWR)

New York (LGA)

Orlando (MCO)

San Francisco (SFO)

Dallas/Fort Worth (DFW)

New York (JFK)

Boston (BOS)

Seattle (SEA)

Baltimore/Washington, DC (BWI)

Fort Lauderdale (FLL)

Minneapolis (MSP)

Detroit (DET)

Tampa (TPA)

Philadelphia (PHL)

Phoenix (PHX)

Hopper calculated its numbers based on trips that have already been booked as well as other travel plans passengers are expected to book based on search data. Hopper collects information from Global Distribution System data sources, including 10 million queries and 1 billion trips per day.

AAA Travel is also forecasting a rise in holiday travel, with 41 million Americans making trips of 50 miles or more between July 2 and July 6. That's a 1.9 percent increase over 2013.

However those extra trips are in part due to a "willingness to take on credit card debt, not an increase in income," according to the AAA forecast.

The busiest travel weekend arrives amid the busiest summer travel season in years, as airline profits are up, and planes are more crowded.

"Don't put fireworks in your carry-on or checked baggage."

By no coincidence, the U.S. Travel Association, which is lobbying Congress to commit to more transportation infrastructure spending, has just launched an "I'm Stuck!" app. It allows travelers delayed at airports or on the roads to get in touch with their elected officials.

"The Highway Trust Fund is running on fumes and Congress is running out of time," Ed Rendell, the former governor of Pennsylvania and the co-chair of Building America's Future, said in a statement Tuesday announcing the complaint tool. "Our app gives the American people the ability to send a clear message directly to their member of Congress: Act now."

The weather could be a contributing factor to those delays, at least on the Eastern seaboard. While the airlines aren't yet issuing advisories about the tropical storm, the Federal Aviation Administration has one key piece of advice: "Don't put fireworks in your carry-on or checked baggage."